Device for roasting sulphur containing substances, especially metal sulphides containing ores



.1 13,]193L. H. KLE'NCKE 1,788,767

DEVICE FOR ROASTING SULPHUR CONTAINING SUBSTANCES, ESPECIALLY METALSULPHIDES CONTAINING ORES Filed Sept. 15. 1928 2 Sheets-Sheet. 1

' H. -KLENCKE e SULPHUR -coNTA INING YSUBSTA METAL SULPHIDES CONTAININGORE Filed Sept. 15, 192s Jan;l3,-.l93l

DEVICE FOR ROASTIN ESPECIALLY 2 Sheets-Sheet 2 Patented Jan. 13, 1931UNITED "STATES,

ATE-N OFFICE.

HANS KLENC'KE, or rRANk'roRT oNaHE-Miam, GER1VIANY DEVICE FOR ROASTINGi-SULPHUR CONTAINING SUBSTANCES, ESPECIALLY METAL SULPHIDES CONTAININGORES 4 Application filed September 15, 1928, Serial No This inventionrelates to a method and a device for roasting sulphur-containingsubstances especially metal sulphides containing ores.

When roasting sulphur containing raw materials such as pyrite, zincblend or the like in mechanical roasting furnaces, it is usual to letthe material-to be roasted drop as seldom as possible and to make thedrop as low aspossible from one flonr to the other floor of the furnace,in order to avoid an excessive formation of dust. The removal of thesulphur from the ore took .place therefore generally only on thehorizontal floors of the furnace; one could however clearly notice aflaming up of the material, when it dropped from one floor to the otherfloor in the furnace. This flaming up was due to an acceleratedcombustion produced by the thorough mixture of the material with theoxygen of the air present in the furnace. It could further be noticed,that the different floors of the furnace were never equally bright, andthat the combustion of the material passing across one fioor was slowlydecreasing during its passage and only revived by the dropping upon thenext floor.

The improvement however of the dust collecting devicesmakes itunnecessary .to work under such conditions, that the formation of dustis avoided; operations may therefore be conducted in such a manner, thatdust is formed, as the dust collecting apparatus especially theelectrodynamic apparatus have "been so perfected, that it is absolutelyimmaterial, whether the furnace makes more or less dust.

\Vhereas formerly more than 7 or 8 floors were not used in mechanicalroasting furaces there is no trouble nowadays to increase the floors to10 and 12.' The increase in the capacity of mechanical roasting furnacesby applying more floors than before may be further raised by using fallopenings on 306,267, and in Germany September 13, 1927.

the floors not only at the periphery and in the center of the furnace,as was hitherto the case, but also between these two places, thusproviding the whole roasting surface of the floors with fall openings,which are arranged irregularly or centrally around theshaft of thefurnace. By this arrangement of the fall openings the mixing of' thematerial to be roasted with the oxygen dropping stream of the materialonly contacted-with a vertically raising gas stream,

whereas according to the new, arrangement it is possible to let the gasstream horizontally pass through the vertically .dro'pping stream of thematerial.

The arrangement of fall openings between the usual fall openings, thatis between the periphery and the centre of the fioor makes it possible,for the middle part of the furnace to be fed with material having ahigher sulphur content than the material which formerly passed acrossthe whole fioor. Thus the main combustion zone of the furnace isenlarged and the capacity of the furnaces may be raised.

By the use of insertion pieces of ceramic material, iron alloys or thelike the size of the openings in the floors may be regulated; theinsertion pieces may also be used to close some openings entirely.

In the old mechanical roasting furnaces air was introduced at the lowestfloor and in about the middle of the floors. With the new mechanicalroasting furnaces, having fall openings all over the floors and agreater number of floors, one may introduce air at one, two, three ormore places as may be desirable for obtaining a good desulphurizationand a great production.

The annexed drawings show a mechanical roasting furnace according to theinvention by way of example.

' *In the drawings,

Fig. 1 is an elevation in partial section of the furnace;

,Fig. 2 is a detail in partial section of one chamber of the furnace; v

Fig. 3'-is a section on line 3 3 of Fig. 2; and

Fig. '4 is a horizontal section on line 4-4 of Fig. 2. 1

The furnace has ten floorsI-X. A is the exterior wall of the furnace, Bthe shaft of the furnace provided with stirrers R on each of the tenfloors. The ore enters the first floor of the furnace by the opening Eand is slowly moved from floor to floor by the stirrers. Besides thenormal fall openings F around the shaft and besides theusual fallopenings G at the periphery of the floor there are arranged someadditional fall openings H in several floors. Especially the floorsin'the middle of the furnace are provided with the greatest number ofadditional fall openings H. flhe main amount of air is introduced intothe furnace in the usual manner through the hollow shaft B by a fan andby a tubing L. The additional openings L L L ,may be used for addingfurther amounts of air. I The gases obtained by the roasting processleave the furnace at S, whereas the roasted ore leaves the furnace at Nat the bottom. The shaft is driven in usual manner and the drivingarrangement has therefore not been floors of the furnace. Thus forexample one or two oil burners may be arranged in the lowest floor asshown in Fig. 2.

I claim from the center to the periphery and from the periphery to thecenter of alternate floors, a floor provided with auxiliary openingsintermediate the periphery and the center of the floor in addition tothe principal openings at the center and the periphery of alternatefloors respectively.

In testimony whereof I afiix my signature.

I HANS KLENCKE.

'1. A mechanical roasting furnace of the type comprising a plurality offloors and a rabble arm on each fioor adapted to move the material to beroasted alternately from thecenter to the periphery and from theperiphery to the center of alternate floors, wherein atleast some of thefloors of the furnace are provided with auxiliary open- Y ingsintermediate the periphery and the center of the floors in addition tothe principal openings at the center and the periphery of alternatefloors, respectively.

2. In a mechanical roasting furnace of.

